title: Abnormal T-wave axis is associated with coronary artery calcification in older adults.
abstract: OBJECTIVE
  To determine whether T-wave axis on the resting electrocardiogram (ECG) is associated with coronary artery calcification (CAC) score, a measurement of coronary atherosclerosis, in older adults.
  
  
  METHODS
  The sample consisted of 2004 adults aged 66 and over participating in the prospective, population-based Age-Gene/Environment Susceptibility-Reykjavik Study. The cohort was divided into gender-stratified quartiles based upon Agatston CAC score derived from computerized tomography. Frontal T-axis deviation from 45 degrees was assessed using surface ECG. Statistical analysis was performed with Tobit regression models adjusted for demographic and cardiovascular risk factors.
  
  
  RESULTS
  In the entire study population, T-axis deviation from 45 degrees was significantly associated with increasing CAC score in men (p<0.001) and women (p=0.03). In men without clinically recognized coronary heart disease (CHD), the association with CAC score remained statistically significant (p=0.02). This association was significant among women without CHD once male CAC cut points were used (p=0.05).
  
  
  CONCLUSIONS
  An abnormal T-wave axis is associated with an increasing CAC score in this population of Icelandic older adults. This association remains in the subgroup of subjects without clinical CHD.
authors.affiliation: National Institute on Aging, Laboratory of Epidemiology, Demography, and Biometry, NIH, Bethesda, MD, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Scherer
authors.forename: Thor
authors.initials: T
authors.lastname: Aspelund
authors.forename: Sigurdur
authors.initials: S
authors.lastname: Sigurdsson
authors.forename: Robert
authors.initials: R
authors.lastname: Detrano
authors.forename: Melissa
authors.initials: M
authors.lastname: Garcia
authors.forename: Gary F
authors.initials: GF
authors.lastname: Mitchell
authors.forename: Lenore J
authors.initials: LJ
authors.lastname: Launer
authors.forename: Gudmundur
authors.initials: G
authors.lastname: Thorgeirsson
authors.forename: Vilmundur
authors.initials: V
authors.lastname: Gudnason
authors.forename: Tamara B
authors.initials: TB
authors.lastname: Harris
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002114:Calcinosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D007055:Iceland; D016015:Logistic Models; D008297:Male; D011159:Population Surveillance; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed